JP2009245833A - Lighting fixture for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting fixture for a vehicle which is compact and can achieve a sufficient radiating effect and in which fixing and alignment are easy and a displacement can be prevented. <P>SOLUTION: A heat sink 20 is composed on a side of a rear end of an LED base board 11 and around a circumference of a reflection surface 17 of an optical component 15. Then the heat sink 20 can achieve a sufficient heat radiating effect in a compact structure. A recess 21 provided in the heat sink 20 has an inner circumferential surface 23 identical to a shape of the reflection surface 17 of the optical component 15. As a result, when the optical component 15 is coupled with the recess 21, the alignment can be performed easily and the occurrence of the displacement can be prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicular lamp suitably used for a light source such as a light emitting diode.

  In general, a light source such as a light emitting diode (LED) can be handled as a point light source, and has an advantage of low power consumption and long life. Therefore, in recent years, with increasing output of LEDs, many techniques for applying LEDs as a light source of a vehicular lamp have been proposed.

  In such a vehicular illumination lamp, in order to improve forward visibility, it is desirable that the light distribution pattern formed by light irradiation is a horizontally long light distribution pattern with a large horizontal diffusion angle. For example, Patent Document 1 proposes a technique that enables light from an LED to be formed into a horizontally long light distribution pattern with a large horizontal diffusion angle by using a translucent member.

As the translucent member, one made of resin or glass is employed. In order to reduce the cost, the translucent member is often made of a resin such as an acrylic resin. However, the resin translucent member is thermally deformed at a relatively low temperature. For this reason, in the proposal of Patent Document 1, a heat sink is provided behind the LED substrate.
JP-A-2005-228502

  However, in the proposal of Patent Document 1, in order to obtain a sufficient heat dissipation effect, it is necessary to arrange a large heat sink behind the LED substrate, and there is a problem that a large area is required for this purpose.

  An object of the present invention is to provide a vehicular lamp that can suppress heat generation of a lamp by a sufficient heat dissipation effect without requiring a large area, can be easily mounted and aligned, and can prevent displacement. And

  The vehicular lamp of the present invention has a light source, an optical member disposed in front of the light source, a rear end attached to the light source, and a recess that fits into the optical member, and is disposed around the optical member. And a heat sink to be provided.

  According to the present invention, it is possible to suppress the heat generation of the lamp by a sufficient heat dissipation effect without requiring a large area, and it is possible to easily attach and align and prevent positional deviation.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  1 and 2 relate to a first embodiment of the present invention, FIG. 1 is a cross-sectional view showing a main part of a vehicular lamp, and FIG. 2 is an exploded perspective view showing a main part of the vehicular lamp.

  1 and 2, a vehicular lamp 1 includes a light source using a surface-mounted light emitting diode (LED) 12, an optical component 15, and a heat sink 20. For example, the vehicular lamp 1 can be used as a vehicular headlamp or a fog lamp. it can. LED12 is arrange | positioned at the LED board | substrate 11 which makes a planar substantially rectangular shape, for example. The LED substrate 11 holds the LEDs 12 by soldering or the like, and electrically connects the held LEDs 12 to a power supply circuit (not shown).

  For example, the LED 12 can be configured by a high-power white LED that obtains white light by applying a yellow phosphor such as a YAG phosphor on the surface of an element having a blue light-emitting portion. The emitted light from the LED 12 is emitted forward through the optical component 15.

  The optical component 15 includes, for example, a concave incident surface 16 that surrounds the LED 12, a reflective surface 17 that totally reflects incident light from the incident surface 16, and an incident surface on the surface of a transparent member made of transparent resin or glass. A main part is configured by forming an output surface 18 for emitting direct light incident from 16 and reflected light reflected by the reflecting surface 17.

  More specifically, the incident surface 16 has a planar first incident surface 16a that directly faces the emission surface of the LED 12, and a circumferential surface shape in which a tip portion is continuous with a peripheral portion of the first incident surface 16a. The first and second incident surfaces 16 a and 16 b form a recess on the base end surface of the optical component 15. Here, the second incident surface 16b is formed coaxially with the optical axis of the optical component 15, and is linearly expanded from the distal end side to the proximal end side. The incident surface 16 surrounds the LED 12 when the base of the optical component 15 is fixed to the LED substrate 11. As a result, a light beam with a small radiation angle emitted from the LED 12 enters the optical component 15 through the first incident surface 16a, and a light beam with a large radiation angle enters through the second incident surface 16b. The reflecting surface 17 is set on the peripheral surface around the optical axis of the optical component 15. The reflecting surface 17 mainly reflects the light incident through the second incident surface 16 b and guides it to the tip side of the optical component 15.

  The emission surface 18 is set to the tip surface of the optical component 15. The exit surface 18 is a combination of a first exit surface 18a set at a substantially central portion of the front end surface of the optical component 15 and a second exit surface 18b set at a peripheral portion of the first exit surface 18a. It is configured. The first exit surface 18a is formed of a spherical convex lens surface having a substantially circular shape as a base, and mainly emits incident light from the first entrance surface 16a. On the other hand, the second emission surface 18b is formed of, for example, a plane orthogonal to the optical axis, and mainly emits reflected light from the reflection surface 17.

  Hereinafter, the LED substrate 11 side in the optical axis direction is referred to as the rear, the emission surface 18 side is referred to as the front, and the direction perpendicular to the optical axis is referred to as the up / down or left / right direction.

  In the present embodiment, a heat sink 20 is attached to the LED substrate 11 in order to improve heat dissipation. The heat sink 20 is made of a metal material having a high thermal conductivity. The heat sink 20 is a substantially rectangular parallelepiped housing having a recess 21 having a front opening at the center. By housing the optical component 15 in the recess 21, the heat sink 20 is configured to surround the LED substrate 11 and the optical component 15 from the rear side of the LED substrate 11. That is, the heat sink 20 has the same size as the front end surface of the optical component 15 on the front side, and has a size slightly protruding from the rear side of the LED substrate 11 on the rear side. The component 15 has substantially the same size as the emission surface 18 of the component 15.

  That is, the heat sink 20 is configured to have a sufficient capacity in a relatively narrow region. Further, the heat sink 20 has fins 24 formed on the outer surfaces other than the front surface.

  The bottom surface 22 of the recess 21 of the heat sink 20 is formed in a flat shape, and the LED substrate 11 is attached on the bottom surface 22. The LED substrate 11 is sufficiently radiated by being attached to the bottom surface 22 of the heat sink 20.

  In addition, heat dissipation can be further improved by comprising the LED board 11 with an aluminum board | substrate etc. with high heat conductivity, for example. The LED substrate 11 and the heat sink 20 may be configured as an integral member.

  Further, the recess 21 of the heat sink 20 has a shape in which the inner peripheral surface 23 matches the peripheral surface shape of the reflecting surface 17 of the optical component 15, and the front side is expanded. From the front side, the optical component 15 can be fitted into the recess 21 while the reflecting surface 17 of the optical component 15 is along the inner peripheral surface 23 of the recess 21. That is, the optical component 15 is positioned in the optical axis direction and the direction perpendicular to the optical axis by being fitted into the recess 21 of the heat sink 20.

  The heat sink 20 is configured not only at the rear end side of the LED substrate 11 but also around the optical component 15 in front of the LED substrate 11 and has a sufficient heat capacity. The heat sink 20 has a shape that matches the outer shape of the optical component 15 around the optical component 15 and has a sufficient capacity in a relatively small area. Thereby, the heat sink 20 can effectively dissipate heat generated by the LED 12 while having a compact structure.

  As described above, in the present embodiment, by using the heat sink that surrounds the optical component, it is possible to obtain a sufficient heat dissipation effect while suppressing an increase in the vertical and front-back dimensions. There is no need to provide a large heat sink for the heat radiation design, and the entire lamp can be made thin. Further, it is possible to align the LED and the optical component simply by fitting the optical component into the heat sink. Further, the LED, the heat sink, and the optical component can be easily fixed, and the occurrence of displacement can be prevented.

  The present embodiment can also be applied to a vehicular lamp having an alignment characteristic required as a traveling beam for a vehicle, that is, an alignment pattern that is substantially parallel in the vertical direction and diffuses in the horizontal direction. . FIG. 3 is an explanatory view showing an optical component suitable for such an orientation pattern. FIG. 3A is a plan view of the optical component viewed from the exit surface side, and FIGS. 3B and 3C are FIGS. It is sectional drawing which follows the bb line and cc line of (a).

  As such an optical component 35, as shown in FIG. 3, the reflection surface 17 and the first emission surface 18a are formed as asymmetric aspherical surfaces in the X-axis direction and the Y-axis direction, and It is conceivable that the light distribution characteristics are different between the X-axis direction and the Y-axis direction.

  That is, the shape of the reflecting surface 17 is an aspherical surface that is asymmetric in the biaxial direction perpendicular to the optical axis. For example, the reflecting surface 17 has a minor axis set in one axis (Y axis) direction orthogonal to the optical axis O and oriented substantially in the vertical direction of the vehicle body, and is orthogonal to the optical axis O and oriented substantially in the vehicle width direction. It is formed of an aspherical surface that has a substantially elliptical shape with a major axis set in the direction of the other axis (X-axis) and expands nonlinearly from the base end side to the tip end side.

  The first light exit surface 18a is formed of, for example, an aspherical convex lens surface having a major axis in the X-axis direction and a minor axis in the Y-axis direction and based on a substantially elliptical shape. Incident light from the incident surface 16a is emitted. On the other hand, the second emission surface 18b is formed by, for example, a plane orthogonal to the optical axis O, and mainly emits reflected light from the reflection surface 17.

  According to such an optical component 35, the reflecting surface 17 and the first emission surface 18a are formed as aspherical surfaces that are asymmetrical in the X-axis direction and the Y-axis direction orthogonal to the optical axis O, and the X-axis direction and the Y-axis. Since the light distribution characteristics of the light beam are different from each other in the axial direction, a single light source unit 10 forms a light flux having a desired light distribution pattern. Thus, the light beam formed by the optical component 35 becomes a light beam that is longer in the vehicle width direction than in the vertical direction of the vehicle body in the vicinity of the light collecting portion.

  In the present embodiment, even when such an optical component 35 is employed, the inner peripheral surface 23 of the recess 21 of the heat sink 20 is configured to have a shape portion that matches the shape of the reflection surface 17 of the optical component 35. To do. As a result, the optical component 35 is fitted into the recess 21 of the heat sink 20 so that the LED 12 and the optical component 35 can be aligned.

  FIG. 4 is an explanatory view showing a second embodiment of the present invention. 4A is a plan view showing the vehicular lamp according to the second embodiment, and FIG. 4B is a cross-sectional view taken along the line dd in FIG. 4A.

  In the present embodiment, a vehicular lamp that requires a relatively large amount of light is configured by combining a plurality of vehicular lamps of the first embodiment.

  The vehicular lamp 50 is configured by arranging a plurality of vehicular lamps 1 in FIG. Each vehicular lamp 1 is arranged in a line in the horizontal direction, for example, with the emission surface facing the same plane. And the outer cover 41 is attached to the output surface side of each vehicle lamp 1. The outer cover 41 has an opening 42 that exposes the emission surface of each vehicular lamp 1. In the outer cover 41, the mesh region 43 other than the opening 42 is configured in a mesh shape so that air can be circulated.

  The outer cover 41 is attached to the vehicular lamps 1 arranged in a row so that the emission surface is exposed at the opening 42. The outer cover 41 is attached to the front surface of the vehicle body, for example.

  According to such a configuration, when the vehicle body travels forward, air flows from the front of the vehicle body toward the heat sink 20 via the mesh region 43. As a result, an air flow is generated in the vicinity of the heat sink 20 to promote heat dissipation of the heat sink 20 and to have a sufficient cooling effect.

  In the example of FIG. 4, the example in which the outer cover is attached to the emission surface of the plurality of arranged vehicle lamps has been described, but the outer cover may be attached to the emission surface of one vehicle lamp. Even in this case, it is apparent that the heat dissipation effect can be promoted by flowing air to the heat sink side by the mesh region provided in the outer cover.

  Thus, in the present embodiment, an outer cover that allows air to flow into the heat sink is used, and a sufficient heat dissipation effect can be expected.

  FIG. 5 is an explanatory view showing a modification of the second embodiment. In the modified example of FIG. 5, a ventilation pipe 51 is configured by a partition 50 at the rear of each vehicle lamp 1a, 1b, 1c. The ventilation pipe 51 guides the air flowing in through the mesh region 43 of the outer cover 41 to the ventilation hole 52. The air that has flowed into the heat sink 20 through the mesh region 43 flows vigorously in the vicinity of the heat sink 20 through the ventilation pipe 51, further promoting the heat dissipation of the heat sink 20.

  The heat sink 20 of each vehicle lamp 1a, 1b, 1c is formed so that the fins 24a, 24b, 24c protrude along the flow of air, and air easily flows to each part of the fins 24a, 24b, 24c, A sufficient heat dissipation effect can be expected.

  In addition, each of the vehicular lamps 1a, 1b, 1c has fins 25a, 25c formed only on the side surfaces of both ends of the vehicular lamps 1a, 1c arranged at both ends, and on the opposite side surfaces of each vehicular lamp 1a-1c. Can be integrally formed easily by adopting a structure that does not form fins.

  FIG. 6 is a sectional view showing a third embodiment of the present invention. In FIG. 6, the same components as those in FIG.

  The present embodiment is different from the first embodiment in that a heat insulating member 61 and a concave portion 62 are provided. A heat insulating member 61 is disposed between the reflecting surface 17 of the optical component 15 and the inner peripheral surface 23 of the recess 21 of the heat sink 20. The heat insulating member 61 prevents the heat of the heat sink 20 from being transmitted to the optical component 15 via the reflecting surface 17.

  Further, the bottom surface 22 of the heat sink 20 is provided with a concave portion 62 at the edge portion. The concave portion 62 is formed in a groove shape along the outer periphery of the bottom surface 22, and prevents the bottom surface of the optical component 15 from contacting the bottom surface 22 of the heat sink 20 and the LED substrate 11. Thereby, the heat of the heat sink 20 is prevented from being transmitted to the optical component 15.

  As described above, in the present embodiment, the same effect as in the first embodiment is obtained, and the heat of the heat sink 20 is prevented from being transmitted to the optical component 15 by the heat insulating member 61 and the concave portion 62. be able to. Thereby, even when a resin optical component is employed as the optical component 15, it is possible to prevent the optical component 15 from being damaged by heat. Thereby, even when the temperature of the LED substrate 11 rises to about 100 ° C., for example, the optical component 15 is not damaged.

Sectional drawing which concerns on the 1st Embodiment of this invention and shows the principal part of the lamp | ramp for vehicles. The disassembled perspective view which shows the principal part of the vehicle lamp concerning the 1st Embodiment of this invention. Explanatory drawing which shows the optical component suitable for an orientation pattern. Explanatory drawing which shows the 2nd Embodiment of this invention. Explanatory drawing which shows the modification of 2nd Embodiment. Sectional drawing which shows the 3rd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle lamp, 11 ... LED board, 12 ... LED, 15 ... Optical component, 17 ... Reflecting surface, 20 ... Heat sink, 21 ... Recessed part, 22 ... Bottom surface, 23 ... Inner peripheral surface, 24 ... Fin.

Claims (3)

A light source;
An optical member disposed in front of the light source;
A heat sink attached to the rear end of the light source, and having a recess that fits into the optical member, and disposed around the optical member;
A vehicular lamp characterized by comprising:   The vehicular lamp according to claim 1, further comprising a cover having an opening for exposing the optical member and a hole for allowing air to flow into the heat sink. A heat insulating member disposed between the optical member and the heat sink;
2. The vehicular lamp according to claim 1, further comprising a concave portion that is provided on a bottom surface of the concave portion of the heat sink and forms a gap between the bottom surface of the concave portion and the bottom surface of the optical member.

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